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At least 145 records · Page 8Linked to original sources
PubMed2006

The usage of video analysis system for detection of immobility in the tail suspension test in mice.

The Tail Suspension Test (TST) is a commonly used screening method for antidepressants properties of drugs in mice. To date, immobility in the TST was scored live, by an observer, or automatically, using devices in which mouse movements were detected by a strain gauge. In this study we tested whether the EthoVision video analysis system can be used reliably and accurately for automatic recording and scoring of duration of immobility in the TST. First, the duration of immobility in two mouse lines was assessed. Different mobility thresholds of the video analysis system were applied and the results compared with the duration of immobility scored manually. Next, the selected immobility threshold was applied to determine the dose-response curves for the drug venlafaxine. Finally, scores from the video analysis system were compared with scores generated by an electromechanical strain gauge device (Med Associates) and a human rater. It was found that the EthoVision system could reliably and accurately quantify the duration of immobility in the TST. The best setup was an immobility threshold ranging from 2 to 3 percentage change in the object area. The EthoVision system was effective in detecting the differences between the mouse lines and the dose response to venlafaxine. The results obtained using the video analysis system were similar to the scores yielded by a human rater and the strain gauge device.

Animals↗
PubMed1983

Quantitative autoradiography with radiopharmaceuticals, Part 1: Digital film-analysis system by videodensitometry: concise communication.

A simple low-cost digital film-analysis system using videodensitometry was developed to quantitate autoradiograms. It is based on a TV-film analysis system coupled to a minicomputer. Digital sampling of transmitted light intensities through the autoradiogram is performed with 8-bit gray levels according to the selected array size (128 X 128 to 1024 X 1024). The performance characteristics of the system provide sufficient stability, uniformity, linearity, and intensity response for use in quantitative analysis. Digital images of the autoradiograms are converted to radioactivity content, pixel by pixel, using step-wedge standards. This type of low-cost system can be installed on conventional mini-computers commonly used in modern nuclear medical facilities. Quantitative digital autoradiography can play an important role, with applications stretching from dosimetry calculations of radiopharmaceuticals to metabolic studies in conjunction with positron-emission tomography.

Animals↗
PubMed1995

Application of an image analysis system to the quantitation of tumor perfusion and vascularity in human glioma xenografts.

A semiautomatic method based on a computerized digital image analysis system was developed to quantitate the perfused fraction of blood vessels and the relative vascular area in cross-sections of human glioma xenografts, implanted subcutaneously in athymic mice or intracerebrally in nude rats. The fluorescent dye Hoechst 33342 was injected intravenously to detect perfused tumor vessels. An immunofluorescent staining of Collagen type IV visualized the vascular structures in the same tumor section. Whole tumor sections were automatically scanned twice on a computer-controlled motorized stage of a fluorescence microscope under two different settings of the image analysis system. At the beginning of a scanning session an interactive routine was used to determine the threshold value for segmentation of vascular structures from the darker background. After the first scan a composite image was created, from the individually processed microscopic images, containing the detected vascular structures. The second scan yielded another composite image with objects representing the perfused areas. When both composite images were combined the overlapping structures showed the perfused vessels. Differences in perfused fractions and relative vascular areas were found between different tumors. The reproducibility of this analysis system was tested and evaluated. The method developed here provides a fast and accurate technique for simultaneous quantitative analysis of tumor perfusion and vasculature.

Animals↗
PubMed2003

Image analysis system for assessment of immunohistochemically stained proliferative marker (MIB-1) in oesophageal squamous cell carcinoma.

The prognosis of oesophageal cancer patients is related to the portion of MIB-1 positively stained tumour nuclei. In this study, an image analysis system was developed based on LEICA Image Processing and Analysis System to reduce the subjective, tedious and inaccurate manual counting of nuclei staining. Representative oesophageal cancer tissues were collected and immunohistochemical preparations of MIB-1 were made. The MIB-1 positive nuclei in these tumours were assessed by quantitative counting, semi-quantitative counting, and three computer assessment methods using LEICA QWIN PRO. Our results showed that computer assessment methods were reliable and consistent. The procedure using the system could be accomplished within 15 min. Overlapped or missed counting of nuclei by the observer were eliminated. The image analysis system can really assist experts in obtaining reliable data for the prognosis of oesophageal cancer patients quickly.

Biomarkers↗
PubMed1995

Evaluation on blood platelets by the image analysis system VIDAS 2.5.

This paper introduces a program written on the image analysis system VIDAS 2.5. It enables the automatic quantification of high numbers of adhesion areas of vital human platelets, thus allowing statistical analysis. These adhesion areas were observed by reflection contrast microscopy (RCM), which generates images of an intense contrast and serves as a prerequisite for an evaluation by image analysis. However, RCM-photographs of the observed platelets have highly varying mean greyvalues and greyranges. These common problems for self-operating identification are excluded by two procedures within the program: 1. calibration of the scanning process for an optimal use of the available greyvalues provided by the negative, camera, and the image analysis system; and 2. relation of the threshold for discrimination of adhesion areas to the statistic parameters of the histogram within each individual digitized image. Images processed according to these prerequisites were transferred to the VIDAS implemented routines for identification and measurement of areas. Thus, image analysis combined with RCM offers a tool for basic and clinical platelet research, which is shown by an example of stimulation and inhibited stimulation of platelet activation.

Blood Platelets↗
PubMedDate not supplied

A computerized analysis system for vigilance studies.

A digital signal analysis system for vigilance studies is presented. The analysis is based on adaptive segmentation, band pass filtering, nonlinear eye movement detection and rule-based decision making. A preliminary evaluation of seven subjects falling asleep showed that the system is able to detect small vigilance fluctuations reliably.

Artifacts↗
PubMed2005

[An automatic fluorescence chemosensitivity analysis system for tumors].

The Automatic Fluorescence Chemosensitivity Analysis System (AFCAS), on the basis of image analysis, image recognition and database technologies, automatically collects the microscopic fluorescent images, inputs patient information, processes images, counts cell number, analyzes statistical data, saves and screens the reports and thus it is able to provide effective informations for assisting medical diagnosis and treatments of tumors or cancers. The AFCAS System adopts the image recognition technology of Region Chain Code and Bayesian Classification and ADO-Based database technology.

Algorithms↗
PubMed1992

Comparison of six microcomputer dietary analysis systems with the USDA Nutrient Data Base for Standard Reference.

We compared the general operating features and nutrient databases of six microcomputer dietary analysis systems. A 3-day food record with 73 food items was entered into each program; nutrient averages were compared with the US Department of Agriculture Nutrient Data Base for Standard Reference (USDA NDB), full version, release 9, for microcomputers. The six programs were found to vary widely in cost, number of foods and nutrients in the database, use of non-USDA data and imputation of data for missing values, number of print/export options, time to analyze the 3-day food record, and overall ease of use. Although all of the microcomputer dietary analysis systems were within 7% of the USDA NDB for energy, protein, total fat, and total carbohydrates, the proportion of other nutrients varying more than 15% from the USDA NDB varied considerably between programs. Variance among programs for 3-day food record nutrient values occurred because of differences in the number of food items included in the database (leading to varying degrees of substitution), the recency of the nutrient data (whether or not the most recent USDA releases had been incorporated), and the number of missing values (the degree to which non-USDA sources or estimated calculations were used to fill in the blanks from the USDA standard). Our results demonstrate that it is important for each dietitian to carefully choose a microcomputer dietary analysis system that is suitable to specific and predetermined needs.

Databases, Factual↗
PubMed1992

An interactive image analysis system for quantitative cytology & to classify cervical cells.

Introduction of computers and image analysis systems are gaining faster momentum in order to quantitate the assessment of cells for diagnosis and prognosis, and this system aims to relieve the operator from the tedium of microscopic observation and reduce operator bias and human error. This paper discusses the design and configuration of an interactive image analysis system built in the laboratory for the purpose of cell analysis and classification. The software developed to compute various textural and morphological parameters of cells on smear are briefly described. The results of the experiments carried out to classify normal and abnormal cells on cervical smear show 94 per cent success rate.

Cytological Techniques↗
PubMed1994

Phenobarbital removal characteristics of three brands of activated charcoals: a system analysis approach.

The in vivo phenobarbital removal characteristics of three brands of activated charcoal (Actidose, Charcoaid, Superchar) were studied in normal volunteers using a system analysis approach. The subjects received a 200-mg dose of oral or intravenous phenobarbital followed by a single oral dose of 30 g of one of the three charcoals in a randomized crossover design. The relative merits of the three charcoals in enhancing the removal of oral and intravenous phenobarbital were assessed using a system analysis approach. The removal clearance, time to peak (tp), peak removal clearance (Rmax), percentage of dose removed (PCT infinity), and phenobarbital removal clearance (CLr) were calculated for the oral and intravenous treatments. Superchar had a pulse-like effect, with the shortest tp and the largest Rmax. Actidose and Charcoaid had similar effects, with Actidose inducing slightly greater phenobarbital removal. Superchar has the highest surface area and relative percentage of surface hydroxyl groups, whereas Actidose has the lowest surface area and relative percentage of surface hydroxyl groups of the three charcoals studied. Although correlations between the in vitro and the in vivo phenobarbital adsorption characteristics of the three charcoals may be difficult due to the presence of preservatives and palatibility enhancers in the commercial preparations, it appears that the in vivo effectiveness decreases as the surface area and the concentration of surface hydroxyl groups decrease. The proposed system analysis approach requires fewer assumptions than methods based on compartmental or physiologic approaches and has the advantage of describing the phenobarbital removal in a dynamic manner.

Absorption↗
PubMed1982

On the application of systems analysis to neurophysiological problems.

In this essay we have presented some personal viewpoints on the application of Systems. Analysis to suitable neurophysiological problems and provided reasoned reviews on selected topics (receptor and nerve cell physiology, motor control, vestibular and visual systems) in which new data and ideas were brought about in the past several years by the use of Systems Analysis. Since the nature of the paper precludes the possibility of writing a summary, we simply thank those readers who have endured up to this point. As for those prudent persons who are beginning from this summary, before deciding as to the advisability of taking-up the task, we have a simple advice which runs contrary to the rule stated by the King to Alice in Wonderland (and accepted by one of us; see p. 60): begin from the topic that you like most and eventually go on, using the same criteria, till you are tired: then stop.

Animals↗
PubMed1983

A gait analysis system in clinical practice.

A gait analysis system using a transduced walkway, monitored by microcomputer to measure the time and distance factors of gait, has been in regular clinical use for over two and a half years. The results are easy to understand and have provided objective data which has been found useful in a number of clinical situations. Some of the ways in which the system has been used are described.

Adolescent↗
PubMed1995

Accuracy of three-dimensional linear and angular estimates obtained with the Ariel Performance Analysis System.

Computer-assisted video motion analysis is a method of evaluating human kinematics that offers promise both for research and for clinical application. This study determined the upper limits of accuracy and consistency of linear and angular measures obtained using the Ariel Performance Analysis System. Reference standards included a meter stick and a universal 360 degrees goniometer. Average mean error observed for reconstruction of absolute point estimates was found to be less than 3.5 mm. Mean error estimate for three-dimensional (3D) reconstruction of a linear standard was found to be 1.4 mm (SD 0.30). Average mean angular error observed for 3D reconstruction of goniometer settings 10 degrees to 170 degrees was found to be 0.26 degrees (mean SD 0.21). System users are cautioned that some increased error associated with software derivation of joint angles exists as angles approach 180 degrees, use of wide-angle lens accessories introduces a systematic field-dependent bias; and planar rotation introduces some (< 2 degrees) random error.

Biomechanical Phenomena↗
PubMedDate not supplied

Objective knee evaluation using the Genucom Knee Analysis System. Clinical implications.

The Genucom Knee Analysis System was used in a clinical setting to study the clinical practicality of the Genucom instrument, and the degree of correlation between Genucom and clinical knee examinations. The Genucom evaluation performed by an experienced examiner required 25 to 30 minutes for a 14 test bilateral examination. The instrument provided detailed graphical and tabular data of the test results. One hundred "normal knees" were examined in a series of seven Genucom tests. Normal "laxity bands" for both males and females were generated for a range of load applications for the seven tests. There was no significant difference observed between the male and female laxity distributions. However, a slightly lesser laxity was observed for the male population in general. A group of 38 subjects with 1 injured knee were assessed concurrently using clinical and instrument techniques. Comparisons were made for the 90 degrees anterior-posterior (AP) drawer, the 30 degrees AP drawer (Lachman), and the varus/valgus stress test. For the 90 degrees AP drawer test, 16 subjects were found clinically to have less than or equal to 5 mm of excess laxity based on comparison with the opposite normal knee. The instrumented measurement concurred in 10 cases. In the other six cases it was noted that laxity on the uninjured knee reached the maximum of the "normal" instrumented population, that is with higher than normal laxities. Fifteen subjects were clinically tested with greater than 5 mm of excess laxity. The instrumented test concurred in all but one.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1988

[Characteristics of the debut of exogenously exacerbated paranoid schizophrenia studied by systems analysis].

As a result of a psychopathological total systems analysis of the debut of exogenously aggravated and nonaggravated paranoid schizophrenia the authors have revealed a significant interrelationship allowing the characterization of both general regularities of the "background" effect and individual characteristics secondary to a concrete nature of exogenous impact. Certain peculiarities of the clinical picture and course of exogenously-aggravated paranoid schizophrenia have been identified which may be important for its early differential diagnosis, adequate therapy and prognosis. The authors emphasize the efficacy of the use of a total systems analytical approach to investigating the multifactorial psychopathologic interrelationships.

Chronic Disease↗
PubMed2002

[Research on slit lamp bio-microscope image analysis system].

Slit lamp bio-microscope image analysis system can provide objective and quantitative diagnosis evidences for ophthalmologists and make available efficient storing, management and intercourse of sufferer information and diagnosis results. In this paper, the system is discussed on its devices, software structure, analysis process and algorithm.

Algorithms↗
PubMed2001

Determination of zinc in pharmaceutical products by use of a sequential injection analysis system.

A sequential injection analysis (SIA) system is proposed for the determination of zinc in pharmaceutical samples. The method is based on the spectrophotometric detection of zinc using xylenol orange as a colour reagent at 568 nm. The system can be used to monitor zinc at a frequency of 30 samples h(-1) with an average recovery of +/-98.5% and a relative standard deviation of less than 1%. A linear relationship between peak height and zinc concentration is obtained between 10 and 60 mg L(-1). The results obtained are in good agreement with those obtained by use of a standard method.

Flow Injection Analysis↗